Dissemination of Zoonotic Antibiotic Resistant Serotypes of Salmonella by Caspian Pond Turtles, Golestan and Mazandaran Provinces, Iran

Background: Salmonella spp. are widespread zoonotic pathogens with economic importance for both humans and animals. They are categorized as the natural flora of the gastrointestinal tract of many reptiles. Human salmonellosis acquired from contact with reptiles is a well-recognized medical problem. Objective: The frequency of Salmonella contamination in Caspian pond turtles was surveyed to evaluate the danger of exposure or disease risk for humans as these species are abundant around the villages in Golestan and Mazandaran provinces. Materials and Methods: One hundred fifty fecal samples from Caspian pond turtles were tested by standard bacteriological methods and positive samples were serotyped. Antimicrobial susceptibility tests on isolated Salmonella strains were also performed. Results: Out of 150 samples, 54 turtles were detected to be contaminated with Salmonella. Of the 54 Salmonella isolates, 38.8% (21/54) were serotyped as S. typhimurium; 35.1% (19/54) as S. enterica subsp. enterica; 9.2% (5/54) as S. enterica subsp. salamae; 9.2% (5/54) as S. enterica subsp. arizona; and 7.4% (4/54) as S. enterica subsp. houtenae. Female (28/80, 35%) and male (26/74, 35.1%) turtles showed equal incidence of Salmonella spp. contamination. Resistance was mostly observed against ampicillin (37%) followed by tetracycline (33.3%), nalidixic acid (7.4%), ciprofloxacin (5.5%), and cotrimoxazole (3.7%). The highest susceptibility was observed against gentamicin (100%) and trimethoprim (98.1%). Conclusion: Our findings confirmed that people who are in close exposure to Caspian pond turtles and their feces are at the risk of Salmonella contamination. Accordingly, fundamental principles of hygiene should be applied in human contact with Caspian pond turtles. Furthermore, people should be educated about the Salmonella contamination which may occur through Caspian pond turtles.